<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        function *show() {
            alert(666);

            yield;

            alert(777);
        }

        let geobj = show();
        geobj.next(); // 弹出666
        geobj.next(); // 弹出777
    </script>
</head>
<body>

</body>
<script>

</script>
</html>